397 research outputs found

    Idealness of k-wise intersecting families

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    A clutter is k-wise intersecting if every k members have a common element, yet no element belongs to all members. We conjecture that, for some integer k ≥ 4, every k-wise intersecting clutter is non-ideal. As evidence for our conjecture, we prove it for k = 4 for the class of binary clutters. Two key ingredients for our proof are Jaeger’s 8-flow theorem for graphs, and Seymour’s characterization of the binary matroids with the sums of circuits property. As further evidence for our conjecture, we also note that it follows from an unpublished conjecture of Seymour from 1975. We also discuss connections to the chromatic number of a clutter, projective geometries over the two-element field, uniform cycle covers in graphs, and quarter-integral packings of value two in ideal clutters

    Segmental correction of adolescent idiopathic scoliosis by all-screw fixation method in adolescents and young adults. minimum 5 years follow-up with SF-36 questionnaire

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    <p>Abstract</p> <p>Background</p> <p>In our institution, the fixation technique in treating idiopathic scoliosis was shifted from hybrid fixation to the all-screw method beginning in 2000. We conducted this study to assess the intermediate -term outcome of all-screw method in treating adolescent idiopathic scoliosis (AIS).</p> <p>Methods</p> <p>Forty-nine consecutive patients were retrospectively included with minimum of 5-year follow-up (mean, 6.1; range, 5.1-7.3 years). The average age of surgery was 18.5 ± 5.0 years. We assessed radiographic measurements at preoperative (Preop), postoperative (PO) and final follow-up (FFU) period. Curve correction rate, correction loss rate, complications, accuracy of pedicle screws and SF-36 scores were analyzed.</p> <p>Results</p> <p>The average major curve was corrected from 58.0 ± 13.0° Preop to 16.0 ± 9.0° PO(<it>p </it>< 0.0001), and increased to 18.4 ± 8.6°(<it>p </it>= 0.12) FFU. This revealed a 72.7% correction rate and a correction loss of 2.4° (3.92%). The thoracic kyphosis decreased little at FFU (22 ± 12° to 20 ± 6°, (<it>p </it>= 0.25)). Apical vertebral rotation decreased from 2.1 ± 0.8 PreOP to 0.8 ± 0.8 at FFU (Nash-Moe grading, <it>p </it>< 0.01). Among total 831 pedicle screws, 56 (6.7%) were found to be malpositioned. Compared with 2069 age-matched Taiwanese, SF-36 scores showed inferior result in 2 variables: physical function and role physical.</p> <p>Conclusion</p> <p>Follow-up more than 5 years, the authors suggest that all-screw method is an efficient and safe method.</p

    Comparison of three wet-alkaline methods of digestion of biogenic silica in water

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    Methods for determination of low levels of biogenic silica (0.2–0.4 mg SiO 2 ) in aqueous samples after digestion with three wetalkaline extraction procedures compared favourably in both precision of replicates and recovery of silica utilized by diatoms in budgeted cultures. Leaching samples with 0.2 M NaOH for 10–15 min at 100°C was the least time consuming procedure. Also interference from silicate minerals was lower for this method than leaching with either 0.5 or 5% Na 2 CO 3 for 2 h at 85°C. The use of filters to concentrate samples enables detection of low levels of biogenic silica with colorimetric procedures. Polycarbonate filters are recommended in preference to cellulose acetate or polyvinyl chloride filters for sample collection. Time-course experiments are recommended for establishing digestion times and determining the presence of mineral silicate interference. Wet-alkaline digestion methods are recommended for routine analysis of biogenic silica in suspended matter in preference to infra-red analysis, alkaline fusion and hydrofluoric acid/nitric acid methods.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74725/1/j.1365-2427.1983.tb00658.x.pd

    Cell-free (RNA) and cell-associated (DNA) HIV-1 and postnatal transmission through breastfeeding

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    &lt;p&gt;Introduction - Transmission through breastfeeding remains important for mother-to-child transmission (MTCT) in resource-limited settings. We quantify the relationship between cell-free (RNA) and cell-associated (DNA) shedding of HIV-1 virus in breastmilk and the risk of postnatal HIV-1 transmission in the first 6 months postpartum.&lt;/p&gt; &lt;p&gt;Materials and Methods - Thirty-six HIV-positive mothers who transmitted HIV-1 by breastfeeding were matched to 36 non-transmitting HIV-1 infected mothers in a case-control study nested in a cohort of HIV-infected women. RNA and DNA were quantified in the same breastmilk sample taken at 6 weeks and 6 months. Cox regression analysis assessed the association between cell-free and cell-associated virus levels and risk of postnatal HIV-1 transmission.&lt;/p&gt; &lt;p&gt;Results - There were higher median levels of cell-free than cell-associated HIV-1 virus (per ml) in breastmilk at 6 weeks and 6 months. Multivariably, adjusting for antenatal CD4 count and maternal plasma viral load, at 6 weeks, each 10-fold increase in cell-free or cell-associated levels (per ml) was significantly associated with HIV-1 transmission but stronger for cell-associated than cell-free levels [2.47 (95% CI 1.33–4.59) vs. aHR 1.52 (95% CI, 1.17–1.96), respectively]. At 6 months, cell-free and cell-associated levels (per ml) in breastmilk remained significantly associated with HIV-1 transmission but was stronger for cell-free than cell-associated levels [aHR 2.53 (95% CI 1.64–3.92) vs. 1.73 (95% CI 0.94–3.19), respectively].&lt;/p&gt; &lt;p&gt;Conclusions - The findings suggest that cell-associated virus level (per ml) is more important for early postpartum HIV-1 transmission (at 6 weeks) than cell-free virus. As cell-associated virus levels have been consistently detected in breastmilk despite antiretroviral therapy, this highlights a potential challenge for resource-limited settings to achieve the UNAIDS goal for 2015 of eliminating vertical transmission. More studies would further knowledge on mechanisms of HIV-1 transmission and help develop more effective drugs during lactation.&lt;/p&gt

    Evaluation of arterial anatomy in congenital clubfoot with color doppler ultrasound

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    OBJECTIVE: This investigation intended to evaluate anterior and posterior tibial arteries at the ankle joint level in congenital clubfoot, by using color Doppler ultrasound (CDU). MATERIAL AND METHOD: Twenty patients with idiopathic clubfoot were selected, from which 18 had unilateral involvement and two had bilateral involvement. Of the 18 patients with unilateral clubfoot, 16 went through surgical treatment and the other two were submitted to conservative treatment with serial casting. Of the bilateral cases, one patient was treated surgically and the other was treated with serial casting. All patients were clinically and radiographically assessed. We used the functional rating as described by Lehman. Then, CDU was applied bilaterally at the ankle joint level, trying to identify both posterior and anterior tibial arteries. RESULTS: In our present series of 20 cases with idiopathic clubfoot, in just one patient we could not identify the anterior tibial artery at the ankle joint level. In 12 patients who have had their arterial flow speeds and diameters measured by UDC, a positive correlation was found between functional level and anterior tibial artery diameter. No statistically significant differences were found between both flow speed and diameter of anterior tibial artery of the normal side, when compared to the affected side (in patients with unilateral disease). CONCLUSION: In our sample, we could not find any significant differences in arterial morphology and flow speed between the normal and the affected side. Furthermore, we noticed that the better the clinical result of clubfoot correction, the larger the diameter of anterior tibial artery in affected feet.OBJETIVO: Avaliação ultrassonográfica das artérias tibial anterior e posterior no pé torto congênito (PTC). MATERIAL E MÉTODO: Foram incluídos 20 pacientes portadores de PTC idiopático compreendendo 18 casos unilaterais e dois bilaterais, sendo que 17 pacientes foram submetidos a tratamento cirúrgico e três a tratamento conservador. Todos os pacientes apresentavam pés plantígrados e foram submetidos à avaliação clínica e radiográfica, seguido pelo exame de ultrassom Doppler colorido (UDC), visando a identificação das artérias tibiais anterior e posterior na altura do tornozelo. O nível funcional foi classificado pelos critérios de Lehman. RESULTADOS: Nesta série de 20 pacientes, somente em um não foi identificada a artéria tibial anterior. Nos 12 pacientes submetidos à mensuração de fluxo e calibre pelo UDC, foi encontrada uma correlação positiva entre o grau funcional do PTC e o calibre da artéria tibial anterior. Não houve redução estatisticamente significante entre o fluxo e calibre da artéria tibial anterior do lado normal em comparação com o lado alterado (nos casos de doença unilateral). CONCLUSÕES: Não houve alteração significativa da morfologia e fluxo arterial quando comparamos os lados afetado e normal. Além disso, quanto melhor o resultado clínico da correção do PTC, maior foi o calibre da artéria tibial anterior.UNIFESP Departamento de Ortopedia e TraumatologiaUNIFESP, Depto. de Ortopedia e TraumatologiaSciEL

    Emergence and Persistence of Minor Drug-Resistant HIV-1 Variants in Ugandan Women after Nevirapine Single-Dose Prophylaxis

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    BACKGROUND: Nevirapine (NVP) single-dose is still a widely used antiretroviral prophylaxis for the prevention of vertical HIV-1 transmission in resource-limited settings. However, the main disadvantage of the Non-nucleoside Reverse Transcriptase Inhibitor (NNRTI) NVP is the rapid selection of NVP-resistant virus with negative implications for subsequent NNRTI-based long-term antiretroviral therapy (ART). Here, we analysed the emergence of drug-resistant HIV-1 including minor variants in the early phase after NVP single-dose prophylaxis and the persistence of drug-resistant virus over time. METHODS AND FINDINGS: NVP-resistant HIV-1 harbouring the K103N and/or Y181C resistance mutations in the HIV-1 reverse transcriptase gene was measured from 1 week up to 18 months after NVP single-dose prophylaxis in 29 Ugandan women using allele-specific PCR assays capable of detecting drug-resistant variants representing less than 1% of the whole viral population. In total, drug-resistant HIV-1 was identified in 18/29 (62%) women; rates increased from 18% to 38% and 44% at week 1, 2, 6, respectively, and decreased to 18%, 25%, 13% and 4% at month 3, 6, 12 and 18, respectively. The proportion of NVP-resistant virus of the total viral population was significantly higher in women infected with subtype D (median 40.5%) as compared to subtype A (median 1.3%; p = 0.032, Mann-Whitney U test). 33% of resistant virus was not detectable at week 2 but was for the first time measurable 6-12 weeks after NVP single-dose prophylaxis. Three (10%) women harboured resistant virus in proportions >10% still at month 6. CONCLUSIONS: Current WHO guidelines recommend an additional postnatal intake of AZT and 3TC for one week to avoid NVP resistance formation. Our findings indicate that a 1-week medication might be too short to impede the emergence of NVP resistance in a substantial proportion of women. Furthermore, subsequent NNRTI-based ART should not be started earlier than 12 months after NVP single-dose prophylaxis

    Implementation of a Family Intervention for Individuals with Schizophrenia

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    Families are rarely included in clinical care despite research showing that family involvement has a positive effect on individuals with schizophrenia by reducing relapse, improving work functioning, and social adjustment. The VA QUERI study, EQUIP (Enhancing QUality of care In Psychosis), implemented family services for this population. At two VA medical centers, veterans with schizophrenia and their clinicians were interviewed separately at baseline and 15 months. A family intervention was implemented, and a process evaluation of the implementation was conducted. Veterans with schizophrenia (n = 173) and their clinicians (n = 29). Consent to contact family was obtained, mailers to engage families were sent, families were prioritized as high need for family services, and staff volunteers were trained in a brief three-session family intervention. Of those enrolled, 100 provided consent for family involvement. Seventy-three of the 100 were sent a mailer to engage them in care; none became involved. Clinicians were provided assessment data on their patients and notified of 50 patients needing family services. Of those 50, 6 families were already involved, 34 were never contacted, and 10 were contacted; 7 new families became involved in care. No families were referred to the family psychoeducational program. Uptake of the family intervention failed due to barriers from all stakeholders. Families did not respond to the mailer, patients were concerned about privacy and burdening family, clinicians had misperceptions of family-patient contact, and organizations did not free up time or offer incentives to provide the service. If a full partnership with patients and families is to be achieved, these barriers will need to be addressed, and a family-friendly environment will need to be supported by clinicians and their organizations. Applicability to family involvement in other disorders is discussed

    Understanding the adoption of business analytics and intelligence

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    Cruz-Jesus, F., Oliveira, T., & Naranjo, M. (2018). Understanding the adoption of business analytics and intelligence. In Á. Rocha, H. Adeli, L. P. Reis, & S. Costanzo (Eds.), Trends and Advances in Information Systems and Technologies, pp. 1094-1103. (Advances in Intelligent Systems and Computing; Vol. 745). Springer Verlag. DOI: 10.1007/978-3-319-77703-0_106Our work addresses the factors that influence the adoption of business analytics and intelligence (BAI) among firms. Grounded on some of the most prominent adoption models for technological innovations, we developed a conceptual model especially suited for BAI. Based on this we propose an instrument in which relevant hypotheses will be derived and tested by means of statistical analysis. We hope that the findings derived from our analysis may offer important insights for practitioners and researchers regarding the drivers that lead to BAI adoption in firms. Although other studies have already focused on the adoption of technological innovations by firms, research on BAI is scarce, hence the relevancy of our research.authorsversionpublishe

    Cost of antipsychotic polypharmacy in the treatment of schizophrenia

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    <p>Abstract</p> <p>Background</p> <p>This study compared the costs of antipsychotic polypharmacy for patients who initiated on 1 of the 3 most commonly prescribed atypical antipsychotics – olanzapine, quetiapine, or risperidone.</p> <p>Methods</p> <p>Data were drawn from a large, prospective, naturalistic, multi-site, nonrandomized study of treatment for schizophrenia in the United States conducted between July 1997 and September 2003. Participants who were initiated on olanzapine (N = 405), quetiapine (N = 115), or risperidone (N = 276) were followed for 1 year post initiation and compared on: (a) average daily cost of the index antipsychotic while on the index antipsychotic, (b) average daily cost of the coprescribed antipsychotics while on the index antipsychotic, (c) average daily cost of the index antipsychotic and the coprescribed antipsychotics while on the index antipsychotic, (d) total annual cost of antipsychotic medications prescribed in the year following initiation on the index antipsychotic, using propensity score-adjusted bootstrap resampling method. Average daily antipsychotic costs and total annual antipsychotic costs were also estimated using more recent (2004) antipsychotic drug prices.</p> <p>Results</p> <p>During the 1 year following initiation on the index antipsychotic, the total average daily cost of the index antipsychotic was higher for quetiapine (15.33)thanolanzapine(15.33) than olanzapine (13.90, p < .05) and risperidone (11.04,p<.01),althoughtheaveragedailycostoftheindexantipsychoticwashigherforolanzapine(11.04, p < .01), although the average daily cost of the index antipsychotic was higher for olanzapine (10.08) than risperidone (6.74,p<.01)orquetiapine(6.74, p < .01) or quetiapine (6.63, p < .01). Lower total average daily costs were observed in risperidone than olanzapine or quetiapine. Significantly lower average daily cost of concomitant antipsychotic medications for olanzapine (3.82)comparedtoquetiapine(3.82) compared to quetiapine (8.70, p < .01) or risperidone-initiated patients (4.30,p<.01)contributedtotheloweraveragedailycostofallantipsychoticmedicationforolanzapineinitiatedpatients.Eachdollarspentontheindexantipsychoticwasaccompaniedbyspendinganadditional4.30, p < .01) contributed to the lower average daily cost of all antipsychotic medication for olanzapine-initiated patients. Each dollar spent on the index antipsychotic was accompanied by spending an additional 1.31 on concomitant antipsychotics for quetiapine compared to 0.64forrisperidoneand0.64 for risperidone and 0.38 for olanzapine-initiated patients. A separate intent-to-treat analysis of the total annual antipsychotic cost found a significantly higher total annual antipsychotic cost for quetiapine-initiated patients (5320)comparedtoolanzapine(5320) compared to olanzapine (4536, p < .01) or risperidone ($3813, p < .01).</p> <p>Conclusion</p> <p>Prevalent antipsychotic polypharmacy adds substantial cost to the treatment of schizophrenia. Comparison of medication costs need to address the costs of all antipsychotics. A better understanding of concomitant antipsychotic costs provides a more accurate portrayal of antipsychotic medication costs in the treatment of schizophrenia.</p
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